The present invention relates to the production of electronic devices, particularly in the field of measurement and detection, and has for its object a process for producing a device of the mentioned type, as well as devices thus obtained.
There is already known at present the potting technique to clad electronic components and thereby to ensure their protection. However, this technique is relatively slow and does not permit efficient production, in large quantity, of products of medium or large size. It is moreover limited in terms of diversity of the resulting external shapes and leads, because of the nature of the material used, to products whose mechanical properties (particularly rigidity) and resistance to shock and to chemical aggression are undesirable, even rendering their use impossible, in certain applications, in particular in industry.
Moreover, there is also known the technique of overmolding pieces or articles, by covering them with a layer of thermoplastic material to give them their final shape and to insulate and physically protect the overmolded pieces or articles relative to the environment.
Nevertheless, this technique subjects the overmolded elements to thermal shock (molten material) and mechanical shock (material applied under pressure), which does not permit the use of this technique for sensitive or delicate electronic components, without the risk of damage or breakage of their connections, as the case may be.
The present invention has particularly for its object to overcome the mentioned drawbacks, in particular, but not in a limiting way, in relation to apparatus or instruments for measuring and/or detection for industrial use, integrating sensitive components and requiring effective protection.
To this end, the present invention has for its object a process for the production of a device of the instrument or apparatus type for measuring or detection, particularly for a sensor or detector, consisting essentially in pre-mounting the different components of the device, of which certain are ultimately to be gathered into one or several functional subassemblies, on and/or in a support body, then potting at least partially the resulting pre-mounted assembly, as well as if desired the connection regions with a connection and/or supply cable, to form a substantially monoblock piece, and, finally, overmolding under pressure said potted piece, as well as if desired the proximal portion of the cable, with a thermoplastic material compatible with the resin used, to obtain an apparatus or instrument having the desired shape.